Implement DeleteFile and DeleteDirectory.

chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac.h

Index: chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac.h
diff --git a/chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac.h b/chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac.h
index f77083485cd1c7273008d4980717c4045db0297a..f7a5529587ddddd7efbc74bed29621bd5abb552b 100644
--- a/chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac.h
+++ b/chrome/browser/media_galleries/mac/mtp_device_delegate_impl_mac.h
@@ -54,12 +54,18 @@ class MTPDeviceDelegateImplMac : public MTPDeviceAsyncDelegate {
                  int buf_len,
                  const ReadBytesSuccessCallback& success_callback,
                  const ErrorCallback& error_callback) override;
-  bool IsReadOnly() override;
+  bool IsReadOnly() const override;
   void CopyFileFromLocal(
       const base::FilePath& source_file_path,
       const base::FilePath& device_file_path,
       const CopyFileFromLocalSuccessCallback& success_callback,
       const ErrorCallback& error_callback) override;
+  void DeleteFile(const base::FilePath& file_path,
+                  const DeleteFileSuccessCallback& success_callback,
+                  const ErrorCallback& error_callback) override;
+  void DeleteDirectory(const base::FilePath& file_path,
+                       const DeleteDirectorySuccessCallback& success_callback,
+                       const ErrorCallback& error_callback) override;
   void CancelPendingTasksAndDeleteDelegate() override;
 
   // Forward delegates for ImageCaptureDeviceListener. These are